U.S. Pat. No. 3,562,310 describes the preparation of compounds of the formula [R(CH.sub.2)m]2(OSO.sub.2).sub.p O by the reaction of R(CH.sub.2).sub.m I with sulfur trioxide (SO.sub.3), wherein m is 1, 2 or 3, p is an integer of 2 to 6, and R is perfluoroalkyl. The hydrolysis of these polysulfates to the corresponding alcohol is also described. No mention is made of the use of halogen with the SO.sub.3, nor of the use of a fluorinated olefin in a reaction with SO.sub.3.
U.S. Pat. No. 4,362,672 describes the preparation of difluorohaloacetyl fluoride by the reaction of CF.sub.2 =CFY with SO.sub.3 and bromine or iodine to produce an intermediate compound containing the group XCF.sub.2 CFYOSO.sub.2 wherein X is I or Br and Y is F, Cl, Br or I. The difluorohaloacetyl fluoride is obtained by decomposing the intermediate thermally, optionally in the presence of catalysts. In this patent only fully halogenated (but otherwise unsubstituted) ethylenes are reacted. This is in contrast to the present invention where the (perfluoroalkyl)ethylenes that react with the SO.sub.3 /halogen combination contain no vinylic halogen.
C. G. Krespan and D. A. Dixon, J. Org. Chem., Vol 51, pp. 4460-4466 (1986) describe the reaction of SO.sub.3 with perfluoro-2-butene. In this paper the olefin is fully fluorinated and no halogen is used in combination with the SO.sub.3.
Two publications describe the preparation of halohydrins of mono(perfluoroalkyl)ethylenes, and (usually) their subsequent reaction with base to form the corresponding epoxides. Reaction of the mono(perfluoroalkyl)ethylenes with hypohalous acids (U.S. Pat. No. 2,700,686), or with bromine and acetic acid the presence of mercuric ion [C. Coudures, et al., J. Fluorine Chem., Vol. 24, pp. 93-104 (1984)] are methods of making the mono(perfluoroalkyl)ethylene halohydrins. Other publications such as U.S.S.R. Patent 390,084 [Chem. Abs., Vol. 80, 27084u (1974)] and E. T. McBee and T. M. Burton, J. Am. Chem. Soc., Vol. 74, pp, 3022-3023 (1952) describe the preparation of the halohydrins and epoxides of mono(perfluoroalkyl)ethylenes by other methods. A short "review" of early work on forming epoxides nominally derived from mono(perfluoroalkyl) -ethylenes is found in D. D. Smith, et al., Ind. Eng. Chem., Vol. 49, pp. 1241-1246 (1957). This Smith paper also describes the polymerization of such epoxides and the use of the polymers as low load lubricants. None of these publications uses SO.sub.3, and none mentions the preparation of bis(perfluoroalkyl)ethylene halohydrins or epoxides.
It is an object of this invention to provide novel halosulfonates and sulfates useful as intermediates in the production of mono- and bis(perfluoroalkyl)ethylene halohydrins and epoxides, and to provide novel bis(perfluoroalkyl)ethylene halohydrins and epoxides. It is a further object of this invention to provide an easy and inexpensive process for the preparation of mono(perfluoroalkyl)ethylene and novel bis(perfluoroalkyl) ethylene halohydrins and epoxides, and the intermediate sulfates and halosulfonates, by the reaction of mono- and bis(perfluoroalkyl)ethylenes with SO.sub.3 and a halogen, and other subsequent reactions to produce the desired products Mono- and bis(perfluoroalkyl) ethylene epoxides are useful as chemical intermediates and monomers.